1. Field of the Invention
The invention relates to an ostomy appliance for attachment to the body and for collecting bodily waste discharged from a stoma.
Ostomy appliances are usually in the form of a receptacle, e.g. a bag, pouch or for receiving the waste, connected to an adhesive wafer that can be attached to the skin of the patient. The wafer is typically in the form of a backing layer coated on the skin-facing surface with an adhesive layer and the wafer is further provided with an aperture for accommodating the stoma. The size and shape of said aperture can often be adapted individually to fit the anatomy of the patient.
One of the crucial parts of such appliances is the adhesive wafer. The wafer should be able to fit leak proof around the body opening and have good adherence to the skin without unintended detachment from the skin, but at the same time the wafer should be easy to remove again without damaging the skin. Furthermore, the wafer should be able to follow the movements of the body and be comfortable to wear. The components of the wafer, the adhesive and the backing layer determine these properties.
The adhesive of such appliances is usually a hydrocolloid adhesive coated in a relatively thick layer on a backing layer and combined with the fact that this adhesive has a high modulus, the appliance may be inflexible and bulky to wear.
The wafer of an ostomy appliance may be made softer by exchanging the hydrocolloid adhesive with a softer adhesive. However, providing an ostomy appliance with a soft adhesive may give rise to new problems. Whereas the conventional hydrocolloid adhesive wafer was rather stiff and thereby easy to handle and apply, the soft adhesive wafers are soft and mechanical unstable and may easily fold and stick to itself during application.
When applying an adhesive wafer around a stoma the conventional hydrocolloid adhesive wafers are relatively stable and easy to handle, even when the release liner is removed prior to application. The construction of the current hydrocolloid adhesives in modern stoma care products are carried out in such a manner that the wafer, when the release liner is removed, is stiff enough in order for the product to stay in an almost planar manner. In other words the product does not bend, curl or fold significantly during application.
This is due to the choice of backing layer and adhesive. The backing layer is usually a relatively stiff polymer backing and the adhesive is a polymer based continuous phase filled with particles that add to the modulus of the adhesive. The combination of a high modulus backing and adhesive makes the adhesive wafer very stiff.
Due to the choice of backing layer, a relatively stiff polymer backing layer stabilizes the product in combination with a hydrocolloid adhesive. The presence of an absorbent filler, such as hydrocolloid particles, makes the adhesive stiffer. A polymeric matrix for the adhesive comprising PIB (polyisobutylene), SIS (styrene isoprene styrene block copolymer), resin etc. produces a relatively stiff adhesive.
When the type of adhesive is changed from the highly filled relatively stiff materials to a soft, low or non filled adhesive, the need for a soft backing layer is essential in order to obtain the right properties for the intended use. This makes the adhesive wafer very soft, flexible and unable to hold itself in a relatively planar manner after removal of the release liner. The adhesive wafer itself is so flexible that the side portions of the wafer will bend down with gravity after removal of release liner, resulting in the adhesive to stick to itself, bend, curl or fold and the wafer will be useless.
When placing the ostomy appliance around the stoma the usual procedure is to first adjust and attach the bottom part of the appliance to the abdominal area below the stoma, and afterwards attach the upper part of the appliance.
For soft adhesives removing the entire release liner prior to application makes it difficult to control the adhesive and get it applied in the right position on the abdominal skin without introducing fold or tensions in the adhesive that subsequently could lead to leakage of effluents under the adhesive.
2. Description of the Related Art
Handling soft and/or thin adhesive wafers may be addressed in different ways. The adhesive surface may be covered with a number of release liners or the backing layer may be provided with detachable support means.
The wafer may be provided with two release liners, each covering an area of the product. Hereby, the user can remove one release liner, attach the exposed adhesive surface to the body and then remove the second liner and apply the rest of the wafer, all the way through without touching the adhesive surface with the fingers. This solution is for hygiene purpose and is often referred to a non-touch solution.
Devices for faecal management often comprise two or more release liners in order to ease the application to the curved and complicated perianal area. This has been made to facilitate the fact that the adhesive wafer has to be bent approximately 180 degrees in order to adhere to the buttocks.
Today, conventional ostomy appliances are provided with a single release liner, covering the entire adhesive surface. A non-touch solution is achieved by having a non-adhesive tab or ear on the edge portion of the flange for holding during application without touching the adhesive. The tab or ear may be used to ease detachment of the wafer later. This solution is suited for mechanical stable wafers while soft wafers comprising soft adhesive would be difficult—not to say impossible—to handle with such release liner system.
Thus, there is still a need for an ostomy appliance having a high flexibility and comfort for the user and being easy to apply.